Birthday Sex
by HumanLikeYou
Summary: Sebklaine one-shot/PWP - It's Sebastian's birthday, and Kurt and Blaine have plans to give their boyfriend a memorable evening to celebrate.


**A/N:** I wrote this for my best friend's birthday (which was actually yesterday, but this got a lot longer than I was expecting). It was supposed to be some Sebklaine PWP, but I fail at just writing porn for the sake of porn, so there's a bunch of fluff and loving banter and whatnot, too.

This one-shot story features Blaine, Kurt, and Sebastian in a consensual, loving, long-term, three-way relationship. Food play, very light focus on orgasm denial, slight D/s undertones (with semi sub!Blaine and semi Doms!Kurt!Seb), bottom!Blaine.

For those of you who are getting a story alert for this in your emails who may be following me for my other WIPs, yes, I'm still writing them. School's a bitch. OPITW should be updated soon. :P

Note that this is un-beta'd and I haven't had time to read all the way through in one sitting since I'm about to leave the house again. Sorry for any mistakes.

* * *

Kurt listened hard for the sound of their squeaky apartment door, relying on the old hinges to alert him of Sebastian's return from class. As soon as they gave the signal, Kurt jumped to his feet from the kitchen chair, setting aside the latest issue of Vogue, and hurried over to the oven. It had been cooling for nearly twenty minutes now; the cookies had been finished for thirty, but Kurt wouldn't waste the opportunity to bend over and give Sebastian a perfect view of his ass just because the baking was technically finished.

There was a loud, familiar _thump _in the hallway when Sebastian set down his too-massive law textbooks with a groan, and Kurt absentmindedly gave his hips a little shake as he reached in with an oven mitt to grab the pan of chocolate chip cookies off the rack.

"You're wearing my favorite pair of pants," Sebastian observed, walking up behind him.

"Really?" Kurt asked, "I hadn't noticed." He set down the cookies on the stovetop and turned around, smiling and shamelessly letting his eyes drift down to his '_Kiss the Cook' _apron. "How was class?"

"Pretty lousy," Sebastian admitted while he stepped closer, backing Kurt into the counter, "but I'm feeling much better now, so I honestly don't care."

"Mm, that's good to hear." Kurt slipped his arms around Sebastian's shoulders, not batting an eye when he felt the ground disappear under his feet and his back brushing the blender as he was hoisted up onto the fake marble. "We don't want the birthday boy feeling lousy on his special day."

Sebastian pecked him gently on the lips and reached around to untie the back of the apron, slipping it off and tossing it onto the counter beside them. His hands slipped beneath the hem of Kurt's shirt, casually sliding up and down the sides of his body as he worked the fabric higher and higher up, revealing pale skin with a few hickeys from earlier in the week.

"Do I get a cake for my birthday?" he asked, "Or just cookies?"

"Well… it's not exactly a cake," Kurt confessed, trying to hide an amused smile. Wrinkling his face up, he paused and waited for the shirt to be pulled all the way over his head before speaking again, "but it's still one of your favorite flavors."

"Is my not-exactly-a-cake in the bedroom?" Sebastian guessed.

"_May_be…"

"Was it his idea?" he chuckled.

Kurt nodded, and his eyelids fluttered for a moment as Sebastian's hands wandered up his chest to lightly tease his nipples. "He was so excited when it came to him, Bas. God, you should have seen him. It was pretty much the cutest thing ever."

"I swear if he put another bow tie around his dick like he did last year, I'm gonna laugh so hard I probably won't make it to my next birthday."

Kurt giggled, shifting a bit to try lessening the pressure of his half-hard cock, trapped in Sebastian's favorite pair of pants. "He just wants to make special days memorable."

"Every day is pretty memorable, having boyfriends like you," Sebastian said with a soft smile. Kurt pressed their foreheads together, prying Sebastian's hands away from his skin to lace their fingers together.

"You're sweet."

Sebastian shrugged. "I try."

"C'mon." Kurt scooted forward and landed back on the floor, pulling Sebastian along as they abandoned the cookies and started toward the bedroom. "Let's get some birthday sex for the old man."

"You're older than both of us, Kurt."

"You hush."

"Never."

Kurt was just about to respond when they pulled open the bedroom door. His witty remark died on his lips. Sebastian froze just over the threshold, raising his eyebrows while he swallowed down a bark of laughter. Next to him, Kurt's face was falling into a glare that was only a little playful.

"_Blaine._"

"Hi." Blaine smiled as innocently as he could—a difficult feat given the fact that his naked body, reclined on the bed, was painted with intricate patterns of vanilla cake frosting. A few of the abstract, artistic designs had been tampered with, and the evidence of finger trails and the way Blaine kept licking his lips were clear evidence that led straight to the culprit.

"Blaine Anderson," Kurt sighed, "I work hard for forty-five minutes—resisting the urge to blow you the entire time, I might add—because you asked me to make you look positively delicious for Bas, and this is how you repay me?"

"I look delicious all the time," Blaine countered, "And no one told me it was gonna take Seb an extra hour to get home today. What am I supposed to do when I'm laying here for sixty minutes under strict orders not to move a muscle?"

"_Not move a muscle_," Kurt growled.

Sebastian chuckled, wrapping his arms around Kurt's waist and pressing a soft kiss to his temple. "Hey," he murmured, "No arguments on my birthday. Especially not about icing on our boyfriend."

Kurt let his glare linger on Blaine for a moment longer before he pulled back on the bitch face with a roll of his eyes, turning his head to kiss Sebastian firmly on the mouth. Momentarily distracted, the pair remained occupied in the doorway for nearly half a minute until Blaine pointedly cleared his throat.

"Still here, guys," he announced. "Horny and covered in sticky white stuff that isn't as awesome as your cum..."

Without breaking their kiss, Kurt reached for Sebastian's shirt, expertly undoing each button until the halves of fabric parted and slid down Sebastian's arms to the floor. Kurt's pants were the next to go, though they had to pull away from each other's mouths to work the skinny jeans down his legs.

"Fuck, I love when you don't put on underwear," Sebastian said heavily.

"We all know that's why you love those pants the most," Kurt told him, wrapping a hand around his cock and starting to work it to its full length.

Blaine squirmed a little on the bed, making the drying trails of sugar crack against his skin. "I'm gonna start singing 'Happy Birthday' at an obnoxiously loud volume if you two don't get over here in the next five seconds," he warned.

"A little desperate, B?" Sebastian laughed, starting to unbutton his own slacks while he toed off his shoes.

"That's an understatement," Blaine responded, "I've been hard for the better part of two hours now, imagining my boyfriends naked in bed with me. I have the right to be a _little _desperate."

Kurt finally decided to come to Blaine's rescue while Sebastian finished stripping, joining him on the bed and leaning down to kiss him, brushing his curls back with a gentle hand.

"Do you forgive me for messing with your beautiful icing?" Blaine asked quietly, putting on his best apologetic face.

"I suppose I'll _have_ to forgive you," Kurt said with a dramatic flair, swiping his finger across Blaine's chest and bringing some of the frosting to his mouth. "Sex is so much better when none of us are fighting."

"I love you," Blaine smiled brightly, puckering his lips.

"Love you, too, dork." Kurt kissed him again, sweet and slow. A few seconds in, Blaine's jaw went slack, and he moaned into Kurt's mouth, trying to arch his hips up into the fist wrapped around his cock. Sebastian's free hand held him down, though, and Kurt didn't pull out of the kiss, only deepening it with the introduction of his tongue.

Sebastian watched Blaine's muscles tighten and tense with high-strung arousal, listening to him whine against Kurt's lips every time his thumb slipped over the head of his boyfriend's cock. When he grew tired of the teasing, he pulled his hand away and climbed onto the already crowded mattress. With a wet smack, Kurt and Blaine's kiss came to an end, and Blaine panted for a few long seconds, chest heaving.

"You _do_ look delicious," Sebastian told him with a smirk, "in case you were wondering."

"Feel free to enjoy it, birthday boy," Blaine breathed.

"Is that your roundabout way of begging me to lick every inch of your body?"

Blaine's tongue darted out between his lips while he nodded shamelessly. "Please?"

"Aw, c'mon. You can do better than that," Sebastian teased. Kurt laughed behind his hand, trailing his fingers absentmindedly down Blaine's arm.

"_Please, _Seb?" Blaine attempted again. "Please? I want you to lick off all of this icing and kiss me so I can taste it."

"And then what, honey?" Kurt prompted.

"Fuck me."

Sebastian scratched his nails lightly down Blaine's stomach, digging up trails of white while he made goosebumps rise over Blaine's burning skin. "I get to unwrap you for my birthday?" he asked, seduction on full power. "Mm… I really like that idea."

"Then hurry up!" Blaine pleaded, voice cracking as it rose it volume.

"Shh, baby," Sebastian soothed him with a soft kiss and finally gave in to Blaine's wishes, starting with the icing that dipped down into the curves of Blaine's throat, mouthing around the shape of his Adam's apple that bobbed as he swallowed back a groan. Kurt moved down the bed and flattened his tongue on Blaine's abdomen, rubbing a firm hand down against his hip to keep him still.

There were very few things that Blaine Anderson enjoyed more in life than having both of his drop-dead gorgeous boyfriends paying attention to his naked body, whether it was with their hands, tongues, cocks, or a combination of all three. After having several years of practice, they were both experts at making him fall apart, and as they slowly worked together to clean his skin of Kurt's decoration, Blaine had fight off the temptation of letting himself hurtle toward orgasm. His muscles stayed taught, and he gripped the sheets underneath him so hard that his knuckles turned white.

Sebastian wiped the sweat from Blaine's brow and pressed his fingers down against the vein sticking out near his temple. "Relax," he whispered. "Enjoy it."

"I _am_ enjoying it," Blaine said stiffly, cracking open his eyes. "Trying not to enjoy _too much_."

"Here." Sebastian leaned over his body and reached for the drawer of the bedside table, pulling out a bottle of lube while he fished out a second item. "Would this make it better for you?" he asked, holding up a cock ring for Blaine to see.

"Yes," Blaine gasped, "Fuck. Please, Seb."

"Alright, baby. Just hold on a second." Sebastian squeezed Kurt's shoulder lightly, getting him to reluctantly tear away from Blaine's skin and sit back up, wiping his lips with the back of his hand.

"Taste good?" Blaine asked, the end of his question fading off into a low moan while Sebastian worked the ring into place, making him both relieved and more desperate.

"It's my homemade icing," Kurt said matter-of-factly. "Of course it tastes good. And you should know, since you were eating it earlier," he teased.

"Can I have some more?" Blaine asked. The hidden question in his tone was clear, challenging his lovers to make the action as sensual as they could.

Kurt pursed his lips, seeming to consider Blaine's request. Sebastian didn't have to think for more than two seconds before he came up with an idea, and he swiped a quick finger down Blaine's stomach, collecting some of the last streaks. With a lustful grin, he casually moved his hands between Kurt's legs and wiped it down at the base of his cock, smearing it over the smooth skin that Kurt kept impeccably clean-shaven. "How's that?" he asked knowingly.

"You're a genius," Blaine praised, eyes dark.

"He's a perve," Kurt laughed.

Sebastian shoved at him. "Let's see if you still want to insult me when Blaine's tongue is down there instead of my fingers," he snapped playfully.

"Why didn't you do it to yourself instead?" Kurt wondered aloud.

"Because I want to watch. Duh."

Blaine whined low in his throat, finally having had enough of laying on his back on display. He sat up purposefully, letting Sebastian thread a hand into his hair and pull him over for a kiss before turning away and pressing his palms against Kurt's chest, settling him back against the headboard and nudging his legs apart with a grin.

He wasted no time in bending over and diving in, licking his way up the side of Kurt's thigh and the seam of his leg, drawing a low curse from his throat that made Blaine smirk as he kissed the skin and sucked in the first bit of icing, following the sticky trail with his tongue and purposefully avoiding Kurt's erection. He licked as much of the icing up as he could before Kurt finally seized his curls with a shaking hand.

"C'mon, Blaine. Stop teasing," he begged.

"But you're so tasty," Blaine replied with a laugh.

"Yeah, I know. So suck me off."

"Fine," Blaine feigned annoyance, "But just 'cause I love you."

"You just love dick, Blaine," Sebastian interrupted. Blaine rolled his eyes.

"Correction: I love _your_ dicks. The distinction matters."

Without another word, Blaine sank down around Kurt's length, proving his love as enthusiastically as he could. Kurt's toes curled at the instant pleasure, and Sebastian stared down with wide eyes, trailing his fingers along Blaine's spine while he watched.

"Keep going," he said, grabbing the bottle of lube nearby. "How's the ring feeling, Blaine? You good?"

"Mmmph."

"Good. Ass up, babe," Sebastian urged him with a gentle smack. "You still wanna be fucked?"

"Mmph!"

Kurt laughed at the hearty exclamation, which only made Blaine sink deeper, nudging Kurt's cock into his throat. The laughter died out into a long moan, and Blaine patted Kurt's thigh with his hand as he pulled back for breath, clearly pleased with himself.

"Just in case you couldn't translate that," Blaine said to Sebastian, voice rough and contented, "that was a 'Yes,' and then a 'Fuck, yes, please.'"

"I figured as much, Mr. Cockslut."

"I have no shame in my sexuality," Blaine shrugged, nuzzling against Kurt's navel while he spoke and caught his breath, taking care to hold still while Sebastian began to prep him from behind. "I spent long enough trying to be into girls in middle school—"

"And high school," Kurt interjected.

"_Once,_"Blaine groaned, "When I was wasted and I was coerced into a game of Spin the Bottle—and we weren't even dating yet, so hush. Anyway, that's beside the point… Now that I know who I am I figure I should enjoy it, and luckily I've got two wonderfully endowed gentleman in my apartment who love me so much they almost never turn me down! If that makes me the resident cockslut, I really don't care. Your cocks are worth it."

"Thanks for the Afterschool Special, babe," Sebastian teased fondly, with a shake of his head, pressing two fingers in, "You really are gonna be a great teacher."

"Yeah, but—_ah_, fuck," he squirmed at the slow stretch, "I don't think kindergarteners are gonna need to hear my sexuality talk."

Kurt snorted. "Let's hope not." He scratched soothingly against Blaine's scalp, easing him through the burn of three of Sebastian's fingers, "Think of all the angry parents on the phone."

"They'd probably just be jealous," Blaine joked, kissing the head of Kurt's cock before sliding his lips back around the hard flesh, busying himself with Kurt's pleasure while Sebastian tore open a condom and rolled it on. Showing off his impeccable balance and skill for sexual multitasking, Blaine reached back with his hands and spread his cheeks, completely aware of how much the puckered ring of lube-slicked muscle would tease Sebastian while he rushed to spread lubricant over the condom and move into position.

After checking that he was perfectly aligned, Sebastian rocked forward, sliding in with surprising ease and forcing Blaine further down around Kurt's cock than he was prepared for. With a jerk and a wet, choking cough, he pulled off, pressing his face into the crook of his elbow to stifle the harsh sound.

"God, I'm sorry. You alright, babe?" Sebastian stilled his hips with a bit of difficulty, leaning over to kiss between Blaine's shoulder blades. Blaine nodded, coughing a few more times before he regained control. He wiped the back of his hand over red, swollen lips, smearing his own saliva.

"Fine," he murmured, gratefully leaning into Kurt's hands when they moved to cradle his face, "I'm fine."

"Is the ring getting too tight?" Kurt asked gently, concern in his tone.

Blaine hummed low in his throat, "I can handle it a little longer—can wait 'til Seb's done."

"Mmm, I love you so much," Sebastian wrapped his arms around Blaine's middle, "You're the best, Killer."

"Love you, too, birthday boy," Blaine replied, "Now fuck me like you mean it."

Sebastian didn't need to be told more than once. Lifting himself up off of Blaine's back, he gripped onto his boyfriend's sturdy hipbones and picked up a quick pace. Blaine moved with him this time, well accustomed to the rhythms of his two lovers' body movements. Kurt continued to cradle his head while Blaine adjusted to the speed of Sebastian's thrusts, but as soon as Blaine tugged against his hold and opened his mouth, Kurt let him sink back around his cock, gasping quietly at the return of wet warmth and a heavy, skillful tongue.

"Fuck, Blaine," he breathed, "You're gonna make me come."

Blaine moaned, the sound clearly eager, and Kurt inhaled a sharp breath when Blaine's hand found its way to his balls, massaging and teasing them with expert fingertips. He took Kurt back into his throat and swallowed hard, choking a little on his way back up, but he didn't stop, sucking in heavy breaths through his nose and ignoring the burn in his watering eyes.

Sebastian grunted as he pushed forward, burying himself in as deep as he could go. Blaine shook at the familiar twist of pleasure in his gut when his prostate finally received the stimulation it had been waiting for. He let out a guttural moan from his lungs, and it was almost more than Kurt could stand. One last swirl of Blaine's tongue was all it took to finally make his jaw clench tight while he suppressed a wail, trying not to pull too hard on Blaine's curls while the other man sucked him through his orgasm, swallowing without hesitation.

When Blaine finally slipped off, jaw aching and sore, Kurt slumped down against the headboard and pulled Blaine's head against his stomach, holding him close while he caught his breath and listened to the sound of Sebastian's panting and the slap of colliding skin.

"I need to come." Blaine's voice was hardly audible, muffled against Kurt's body, "Please, I—_oh_, please, I need to come."

"Hold on, honey," Kurt cooed, stroking his cheek. "Just a bit longer."

Blaine whined in protest, but he didn't have the strength to argue, closing his eyes and letting Kurt soothe him while Sebastian continued to press their bodies together with a heavy force.

"Close, Bas?" Kurt asked a few seconds later, unable to pull his eyes away from Sebastian's neck where thick muscles and veins stood defined like a sculpture.

"Y-Yeah…" His reply was raw and shaking, "C'mon, B." Sebastian draped himself back over Blaine's back, struggling to reach down and blindly fumble between Blaine's legs. Blaine hissed at the slightest bit of contact, painfully sensitive from being denied release for so long. Sebastian managed to slide the ring free, and Blaine's face contorted with the effort it took to hold back. "Let go, Blaine, c'mon. Fuck, f-fuck!"

Sebastian's hands curled, and his fingers dug into Blaine's sides while he grounded himself as he tumbled over the edge. A whispered, "Come, Blaine," from Kurt was all Blaine needed to finally lose his well-constructed control, and Kurt continued to hold onto him while his first boyfriend whimpered and gasped with relief.

Blaine's muscles gave into temporary atrophy as soon as they stopped clenching with unavoidable jerks of his hips. He saw stars dotting across his vision while he fell limp, supported by Kurt who slid lower onto the bed and pulled Blaine further into his arms. Sebastian pulled out with a reluctant huff of tired breath, chest heaving. He peeled off the condom and dropped it into the trashcan before running a hand through his sweaty hair and drawing lines down Blaine's back with his fingertips.

"We tired him out," Kurt said with an affectionate expression, twirling Blaine's curls between his fingers.

"_I_ tired him out," Sebastian countered, shooting him an amused, challenging grin.

"_No_," Blaine mumbled.

"What, honey?" Kurt asked, looking down.

"No fighting 'bout who exhausted me most today," Blaine specified, huffing out a chuckle, "You do this every time… You're both perfectly powerful and sexy. Trust me."

"It's my birthday, though," Sebastian reminded. "That means I'm automatically right for 24 hours."

"…Fine," Blaine shrugged weakly. "You win today, Seb. Sorry, baby," he patted his hand lazily against Kurt's thigh, trying to make his half-assed apology sound more sincere.

"You shouldn't use your birthday powers for manipulation," Kurt scolded. "I was thinking about baking you a cake, but now I'm starting to question whether or not you deserve one…"

"Aww, please?" Sebastian crawled closer, taking care not to hit Blaine with his knees on the way. He pressed a slow, insistent kiss to Kurt's lips, holding his gaze with a sincere, soft smile. "Love you."

"Yeah, yeah," Kurt rolled his eyes. "I love you, too. Happy birthday."

"Thanks, babe." Sebastian reached down to massage Blaine's neck, and two hazel eyes opened and peered up at their faces. "How're you feeling?"

"I'd feel better if we could all get some cuddling in before Kurt starts feeling gross and demands a shower."

"I like that idea," Sebastian decided. "I'm using my birthday powers to mandate it. C'mere, Kurt. Family time."

"I don't think your average family bonding times include post-coital cuddling," Kurt chuckled, smiling contentedly while he moved out from underneath Blaine and took up his usual place on the right side of the bed. "That would get weird really fast."

"Yeah, but we're not _the average family_, are we?" Sebastian said pointedly, flopping down on Blaine's left and tangling their ankles together.

"Definitely not. We work it out, though," Kurt mused. "Remember when this was supposed to be a one-time threesome?"

"That didn't work out very well for us," Sebastian laughed.

"Nope," Blaine agreed, "And I'm the glue!"

Sebastian patted Blaine's stomach sweetly, "You _used_ to be the glue, babe. Kurt and I don't need your powerful adhesive affection to stand each other anymore. Right, Hummel?" he teased.

"Right, birthday bitch."

"Too much bantering. Not enough cuddling."

"You're a cuddlewhore, B."

"A cockslut. A cuddlewhore. _Geez_," Blaine rolled his eyes with a dramatic flair, "you're so mean to me."

"If you're unhappy, feel free to leave this relationship any time," Kurt suggested with a smirk, "That was the agreement we all came up with."

Blaine tucked his face against Kurt's shoulder, pouting, "No."

"Good choice."

Several long seconds ticked by before Blaine broke the silence with one last murmur. "Happy birthday, Seb."

"Ditto," Kurt echoed, sticking his free hand out over Blaine's stomach. Sebastian laced their fingers together and snuggled up behind Blaine, yawning into his shoulder.

"Thanks, boys. Love you both."

Kurt and Blaine hummed noncommittal sounds of agreement, finally quieting and letting a few minutes of their evening together slip away in each other's arms.


End file.
